Note: For other reviews, check out Neurotic Psych, Science News, the New York Times, or the Boston Globe.
It took a bit longer
than anticipated to finish Mary Roach's new book
Gulp: Adventures on the Alimentary Canal. Not any fault of hers - the book reads glibly enough, with just enough science to hold my interest (
and just enough yuuuckk for wider audience appeal!).
Other reviews (
see above) have explored the book's structure, which jokes hit or miss, and whether it holds water compared to Roach's other works. I'm going to take a slightly different take:
Gulp is a chemistry love story, wrapped in fart jokes and gallows humor.
As before, I'm just going to jump around to different chapters for moments I unexpectedly learned something about the unique chemistry of taste, smell, digestion, and excretion.
Page 44: "Pyrophosphates have been described [to author Roach] as 'cat crack.'"
(
Finicky eater? Add some phosphates!)
Page 56: "A
serving of liver provides half the RDA for vitamin C, three times the RDA for riboflavin, nine times the vitamin A in the average carrot, plus good amounts of vitamins B12, B6, and D, folic acid, and potassium."
"What's the main ingredient in dog food palatants?
Liver."
Page 73: Huh: L-cysteine extracted from human hair has been used to make fake soy sauce.
Page 110: Baby saliva contains extra lipase, to compensate for "...the newborn's high-fat, 100% whole-milk diet."
Page 111: Fabric softener works by "...ever so gently digesting the fibers" using enzymes.
[
Interestingly, howstuffworks.com, Wikipedia, and Answers.com seem to disagree, attributing the effect to static dispersal]
Page 142: Why does fruit crunch? "When you bite into an apple, the flesh deforms, and at a certain moment the cell walls burst."
Page 175: Oysters go into shock at low pH. Thus, "Researchers who need to sedate crustaceans use seltzer water."
Page 226: Apparently, in the early days of NASA space-flight, researchers expressed real concerns over capsule explosions due to methane and hydrogen gas produced during astronaut digestion.
Page 234: "Bean gas" results from complex oligosaccharides passing through the stomach and fermenting in the small intestine.
Page 245: Three sulfurous compounds contribute to most human flatulence odor: hydrogen sulfide, methanethiol, and dimethyl sulfide (
the redolent-of-farts haze formed after a successful Swern oxidation.)
Page 247:
Bismuth subgallate pills "...reduce 100% of sulfur gas odor, [functioning like an] 'internal deodorant.'"
Page 263: More on hydrogen sulfide, the "...hottest area in biomedicine right now: it's a gastrotrasmitter, a signaling molecule, [and] it has
tremendous therapeutic value."
Page 275: Rats and rabbits engage in
autocoprophagia - eating their own feces - as a method of supplementing vitamins (B5, B7, B12, thiamine, riboflavin) produced only by bacteria in their intestines.
Page 316: When processing "samples" for a stool transplant, a blender is modified to deoxygenate and store the material under nitrogen, thus promoting survival of anaerobic gut bacteria.
Overall, I really enjoyed the book, though I couldn't escape feeling that certain chapters (4, 11, 16?) had been shoehorned in from other projects only tangentially related to these "alimentary adventures." One interesting thing differentiating Roach's writing involves asides* to the reader, giving one the feeling that you're leaning in for a secret bit of wisdom...or an extra-terrible pun.
Seeing that Mary's last few books have dealt with (decidedly dirty) topics like
death and digestion, I can only assume the next book will be titled
Waste, and will uncover the exciting science of garbage and landfills.
If she writes it, I'll be first in line for a copy.
*Seriously, I know I'm supposed to 'kill my darlings' in writing, but I can't resist doing this sometimes...**
**Nor, apparently, can I resist ellipses. Dangit.
Hey there, readers! You may have seen the chatter this morning, or perhaps you've seen Carmen's or Andy Revkin's write-ups?
